肺炎球菌多糖结合疫苗可预防婴幼儿肺部疾病，但对年龄≥65岁的成人肺炎球菌社区获得性肺炎的有效性尚未知。近期发表于《新英格兰医学杂志》(简称NEJM)的一项研究结果或许给我们提供了答案，该研究表明，在老年人中，13价多糖结合疫苗(PCV13)可以有效预防其疫苗型肺炎球菌、菌血症和非菌血症社区获得性肺炎以及疫苗型侵入性肺炎球菌性疾病，但不能预防任何原因的社区获得性肺炎。

        该随机双盲安慰剂对照试验共纳入了84496例年龄≥65岁的成人受试者，旨在评估PCV13在预防疫苗型肺炎球菌社区获得性肺炎、非菌血症和非侵入性肺炎球菌社区获得性肺炎和侵入性肺炎球菌性疾病首次发作的有效性。利用标准实验室方法和特定血清型尿液抗原检测鉴定社区获得性肺炎和侵入性肺炎球菌性疾病。

        结果按方案分析疫苗型模式菌株感染的首次发作显示，PCV13组和安慰剂组分别有49人和90人发生了社区获得性肺炎(疫苗有效性45.6%)，相应地，两组分别有33人和60人发生了非菌血症和非侵入性社区获得性肺炎(疫苗有效性45.0%)，分别有7人和28人发生了侵入性肺炎球菌性疾病(疫苗有效性75.0%)。功效持续至整个实验(平均随访3.97年)。

        在改良意向分析中可观察到相似的有效性(疫苗有效性分别为37.7%、41.1%和75.8%);两组分别有747人和787人发生了社区获得性肺炎(疫苗有效性5.1%)。

        两组的严重不良事件和死亡数相似，但PCV13组的局部反应更多。

        参考文献：Marc J.M. Bonten, et al. N Engl J Med 2015; 372:1114-1125March 19, 2015DOI: 10.1056/NEJMoa1408544

Polysaccharide Conjugate Vaccine against Pneumococcal Pneumonia in Adults
Marc J.M. Bonten, M.D., Ph.D., Susanne M. Huijts, M.D., Marieke Bolkenbaas, M.D., Chris Webber, M.D., Scott Patterson, Ph.D., Samantha Gault, M.B.A., Cornelis H. van Werkhoven, M.D., Anna M.M. van Deursen, M.D., Elisabeth A.M. Sanders, M.D., Ph.D., Theo J.M. Verheij, M.D., Ph.D., Michael Patton, B.Sc., Anne McDonough, M.P.H., Anita Moradoghli-Haftvani, B.Sc., Helen Smith, B.Sc., Tracey Mellelieu, B.Sc., Michael W. Pride, Ph.D., Graham Crowther, Ph.D., Beate Schmoele-Thoma, M.D., Daniel A. Scott, M.D., Kathrin U. Jansen, Ph.D., Rita Lobatto, M.D., Bas Oosterman, Ph.D., Nils Visser, M.Sc., Esther Caspers, M.Sc., Andre Smorenburg, M.Sc., Emilio A. Emini, Ph.D., William C. Gruber, M.D., and Diederick E. Grobbee, M.D., Ph.D.
N Engl J Med 2015; 372:1114-1125March 19, 2015DOI: 10.1056/NEJMoa1408544

BACKGROUND
Pneumococcal polysaccharide conjugate vaccines prevent pneumococcal disease in infants, but their efficacy against pneumococcal community-acquired pneumonia in adults 65 years of age or older is unknown.
METHODS
In a randomized, double-blind, placebo-controlled trial involving 84,496 adults 65 years of age or older, we evaluated the efficacy of 13-valent polysaccharide conjugate vaccine (PCV13) in preventing first episodes of vaccine-type strains of pneumococcal community-acquired pneumonia, nonbacteremic and noninvasive pneumococcal community-acquired pneumonia, and invasive pneumococcal disease. Standard laboratory methods and a serotype-specific urinary antigen detection assay were used to identify community-acquired pneumonia and invasive pneumococcal disease.
RESULTS
In the per-protocol analysis of first episodes of infections due to vaccine-type strains, community-acquired pneumonia occurred in 49 persons in the PCV13 group and 90 persons in the placebo group (vaccine efficacy, 45.6%; 95.2% confidence interval [CI], 21.8 to 62.5), nonbacteremic and noninvasive community-acquired pneumonia occurred in 33 persons in the PCV13 group and 60 persons in the placebo group (vaccine efficacy, 45.0%; 95.2% CI, 14.2 to 65.3), and invasive pneumococcal disease occurred in 7 persons in the PCV13 group and 28 persons in the placebo group (vaccine efficacy, 75.0%; 95% CI, 41.4 to 90.8). Efficacy persisted throughout the trial (mean follow-up, 3.97 years). In the modified intention-to-treat analysis, similar efficacy was observed (vaccine efficacy, 37.7%, 41.1%, and 75.8%, respectively), and community-acquired pneumonia occurred in 747 persons in the PCV13 group and 787 persons in placebo group (vaccine efficacy, 5.1%; 95% CI, −5.1 to 14.2). Numbers of serious adverse events and deaths were similar in the two groups, but there were more local reactions in the PCV13 group.
CONCLUSIONS
Among older adults, PCV13 was effective in preventing vaccine-type pneumococcal, bacteremic, and nonbacteremic community-acquired pneumonia and vaccine-type invasive pneumococcal disease but not in preventing community-acquired pneumonia from any cause.